Boot the canonical Tiny Core Flow stack on Android via Termux QEMU #3

The Android phone VM goal is still useful, but it should follow the repository's current Tiny Core/Linux architecture rather than the retired bespoke Multiboot2 kernel path in PR #2.

Build on the canonical CorePure64/QEMU flow from issue #1. Provide a Termux setup script and runner that boot the pinned Tiny Core image under QEMU TCG on 64-bit Android, carry the existing Flow userspace service and diagnostic contract into that guest, and capture serial output in a form CI can exercise with the same runner.

Prefer an ARM64 guest on ARM64 Android when the Tiny Core target and Flow toolchain support it; x86_64 under TCG can remain a compatibility path where needed.

Acceptance: the Android runner uses the same Tiny Core substrate and health contract as normal flow-kernel CI; no Android bootloader or host-kernel modification is required; a successful phone/CI boot reaches the Flow userspace smoke test; artifacts include the runner, pinned image metadata/checksums, and clear Termux instructions.

Supersedes the architecture used by PR #2 without dropping the Android VM objective.